@tigerpro said in Don't have a microphone? Don't worry, UT can do this for you...:
I wonder if this solution could also be adapted to make sound on a HDMI connected screen work
It cannot. You can of course use a 3.5mm to RCA or such adapter, to connect the headphone jack to the audio input on your TV, to get sound that way, but there is no support in the pulseaudio hybris modules currently for sending audio output over the HDMI when a Slimport/MHL cable is connected.